共查询到20条相似文献,搜索用时 125 毫秒
1.
2.
从GPS测姿与传统测姿进行对比入手,介绍了GPS载波相位测量载体姿态的坐标系及其变换,GPS测姿的两种方法,并对影响GPS测姿精度的误差源进行了分析,最后对GPS测姿在实际应用中存在的问题进行了讨论。 相似文献
3.
4.
5.
6.
7.
针对 MEMS 惯性器件精度较低,MEMS 惯导系统无法满足平台姿态精度要求的问题,本文提出了一种基于 MEMS 器件的测姿、定向方法。当载体近匀速运动时,利用加速度计和磁力计信息,采用垂直陀螺原理得到高精度的姿态信息,通过卡尔曼滤波估计出陀螺漂移,载体非近匀速运动时采用惯性姿态递推更新算法,补偿修正力矩和陀螺漂移误差,提高了载体的测姿定向精度。实验测试结果表明,采用本文的测姿定向方法后 MEMS 系统的姿态精度达到了 0.6°, 精度明显高于传统方法的精度,能够满足大多数中高精度平台的要求。 相似文献
8.
传统的载体滚转角和转速测量方法成本高昂且仅限于高价值平台,为降低成本利用GPS信号测量滚转角的方法日益受到关注。将GPS载波信号的相位和幅度信息用于姿态测量,是目前旋转平台基于GPS测姿的两类主要方法。为了实现旋转载体的低成本高精度滚转角和转速测量,本文提出了单天线结构的利用GPS卫星接收机硬件相关器直接输出的导航用载波I/Q信号幅度特性,设计基于EKF的滚转角滤波器,利用载波I/Q信号的幅度特性对载波频率进行估计与跟踪,从而实现旋转载体的滚转角和转速的精确计算。实测数据试验表明,对于旋转载体仅利用卫星载波I/Q信号的幅度信息,本文提出的算法即可实时计算出旋转载体的滚转角和转速,且计算精度能够满足大多数的实际工程应用。 相似文献
9.
双天线GPS航姿测量系统研究 总被引:1,自引:0,他引:1
本文研究两天线构成的航姿测量系统。该系统采用载波相位双差法进行GPS信号测量,利用直接法来求解载体的姿态。整周模糊度算法采用基于最小二乘法的整周模糊度搜索法,同时利用船舶的低精度姿态信息和预知的基线长度来辅助求解调整周期糊度,以提高求解速度,并增加可靠性,本文的方案经过了实测解算,证明可行。 相似文献
10.
11.
12.
A new method of forming a four-port multi-antenna by a two-unit patch antenna array is proposed to design a high isolation low correlation small size multi-antenna. Dual polarization is realized by the method of feeding in two ports. Defected Ground Structure (DGS) is used to eliminate the coupling between the two antenna units. The test results show that the isolation between two ports reaches around 20dB, and that the antenna correlation coefficients is less than 0. 5, which meets the requirements of future mobile communication systems and provides a solution to multi-antenna of MIMO terminals. 相似文献
13.
14.
海上升空通信中继系统是解决海上广域无线宽带通信的重要手段,但其性能易受海面波动带来的多径衰落影响。为了有效提升中继系统接收信号质量,提出了一种多天线分集接收方法,通过现场可编程门阵列(Field Programmable Gate Array, FPGA)实现相应的接收处理。仿真分析及实验室测试表明,所提出的四天线分集接收技术能够带来近6 dB的合成增益。经海上对比试验验证,采用所提出的多天线分集接收技术的升空通信中继系统,其数据接收完整性提升了10%~20%,系统性能显著改善。 相似文献
15.
A MIMO multi-antenna system of compact double uniform circular array (DUCA) in three dimensional direc-tional frequency non-selective Rayleigh fading channel was analyzed and investigated. Equivalent network model of MIMO multi-antenna array considering MC effect was established, general expressions of correlations were derived and the relationship between correlations with and without MC was classfied. Then, the results were compared with general uniform linear array (ULA) and uniform circular array (UCA). It was concluded that the deployment of antennas plays a decisive role in correlations between antennas. The research has a good sense on designation of spatial massive MIMO multi-antenna array and system optimization. 相似文献
16.
对角加载技术可抑制小特征值对自适应权值的影响来加速自适应波束形成器的收敛性以及抑制导向矢量误差的影响避免信号相消,该技术通常用于稳健的波束形成算法.基于对角加载技术,本文提出了一种信号源数目判定的改进方法,通过对角加载数据协方差阵,可以平滑小快拍数和空间色噪声时的噪声特征值分散程度从而减轻其对信号源数目估计的影响,证明了该估计器的强一致性,分析了加载量对信号源数目估计的影响.最后通过仿真以及实测数据比较了本文方法和已有方法的性能,验证了所提方法的有效性. 相似文献
17.
为了解决用户节点无法安装多个天线的问题,提出了多节点协作通信技术来形成虚拟的多天线阵列。多节点协作是一种新的空间分集方法,不同节点彼此共享天线并相互转发信息来得到分集增益。通过研究多节点协作通信的关键技术,分析多节点协作的性能增益,指明了多节点协作的发展与应用方向。 相似文献
18.
针对"北斗"卫星姿态测量系统在测姿过程中测姿精度和稳定性不高的问题,提出了"北斗"卫星导航系统(BDS)/惯性导航系统(INS)紧耦合姿态测量算法.该算法首先利用BDS观测量设计了BDS系统测姿误差模型;然后以INS状态误差方程为滤波系统状态方程,以载波相位为主要观测量设计了扩展卡尔曼滤波器,利用滤波器的输出实现对惯性导航测姿系统的辅助校正;最后采用静态测试、动态测试和遮挡测试验证该算法.该系统可以有效提高BDS测姿精度与输出频率,并且在静态条件下航向角测量精度可以达到0.15°. 相似文献
19.
20.
Clark E. Cohen E. Glenn Lightsey Bradford W. Parkinson William A. Feess 《International Journal of Satellite Communications and Networking》1994,12(5):427-433
Preliminary space flight results of attitude determination using GPS are presented from a spacecraft in low Earth orbit. Relative position measurements accurate to the sub-centimetre level are made among multiple GPS antennas mounted on the space vehicle. A Trimble Navigation TANS Quadrex (a GPS receiver specially adapted for attitude determination by Stanford University) is used as a differential carrier phase sensor for the flight. Four GPS antennas are mounted on the zenith face of RADCAL, a polar orbiting, gravity-gradient-stabilized Air Force Space Test Program Satellite, built by Defense Systems, Inc. The four antennas are equally spaced about the perimeter of the 30 inch diameter cylindrical spacecraft bus. The Quadrex receiver measures the phase of the L-band GPS carrier (1575 MHz) at each of up to four antennas for up to six GPS satellites simultaneously. From these measurements, an initial assessment of attitude determination in space is performed in post-processing. For RADCAL, the attitude solution is greatly overdetermined. In a preliminary evaluation of system performance, the system accuracy is determined through measurement self-consistency. Analysis of the attitude motion in the context of a gravity gradient dynamic model yields further insight into the system performance. 相似文献